Binder kernel driver: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/lin...
Media codecs: https://www.androidauthority.com/android-16-in-process-softw...
> Rewriting SymCrypt in Rust to modernize Microsoft’s cryptographic library
https://www.microsoft.com/en-us/research/blog/rewriting-symc...
I think they're trying to avoid rewriting things for no reason though. The things being rewritten tend to have a history of security problems or other issues that would be cause for a rewrite even if it wasn't in Rust.